Just a thought Im throwing out there; could the fact I'm burning ... something be affecting my O2 sensor, causing the cel code 43?
P.S. this is what my spark plugs look like
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P.S. this is what my spark plugs look like
Only getting 22mpg HELP!
Hi guys,
After reading the sticky on gas mileage, I've started to replace a few things that could be the culprit to my terrible gas mileage.
Let me start with the specs of my car.
Its a d15b block, d15b7 head, si headgasket (8.55:1 compression)
Automatic transmission
Oem everything.
Tires @ 40psi
No tuning modifications at all.
New NGK Spark Plugs and Wires
Before I was getting an average of 22mpg. I just changed the fuel filter with an autozone replacement and now only got 190 miles out of the next tank of gas!! I verified there's no leaks after the replacement.
I pulled the o2 bung in the cat (obd2 cat on obd1 car, so bung closing the second O2 sensor hole) and it was BLACK as was the exhaust tip.
This leads me to a bad O2 sensor which I am going to change tonight.
I honestly have no clue how to check timing at the distributor, or valve lash so I'll be looking those up shortly after I finish this post. I highly believe it could be the distributor as I noticed recently it was only being held in with 1 bolt. I've since fixed that, so no more oil leaks at least.
From there if anyone has some ideas as to what could be causing such a major drop in economy I'll appreciate the support. I'll also be checking compression and would love to do a leak down test, but I say that term to all the tool rental places around here and they look at me as if I have 3 heads.
Thanks again in advance.
James
P.S. I have an intermitent sputter while the car is warming up, I would go as far as to say it sound like a misfire. NO cel lights
P.P.S I definitely think I have at least a distributor timing issue after reading a thread on how to set it.
After reading the sticky on gas mileage, I've started to replace a few things that could be the culprit to my terrible gas mileage.
Let me start with the specs of my car.
Its a d15b block, d15b7 head, si headgasket (8.55:1 compression)
Automatic transmission
Oem everything.
Tires @ 40psi
No tuning modifications at all.
New NGK Spark Plugs and Wires
Before I was getting an average of 22mpg. I just changed the fuel filter with an autozone replacement and now only got 190 miles out of the next tank of gas!! I verified there's no leaks after the replacement.
I pulled the o2 bung in the cat (obd2 cat on obd1 car, so bung closing the second O2 sensor hole) and it was BLACK as was the exhaust tip.
This leads me to a bad O2 sensor which I am going to change tonight.
I honestly have no clue how to check timing at the distributor, or valve lash so I'll be looking those up shortly after I finish this post. I highly believe it could be the distributor as I noticed recently it was only being held in with 1 bolt. I've since fixed that, so no more oil leaks at least.
From there if anyone has some ideas as to what could be causing such a major drop in economy I'll appreciate the support. I'll also be checking compression and would love to do a leak down test, but I say that term to all the tool rental places around here and they look at me as if I have 3 heads.
Thanks again in advance.
James
P.S. I have an intermitent sputter while the car is warming up, I would go as far as to say it sound like a misfire. NO cel lights
P.P.S I definitely think I have at least a distributor timing issue after reading a thread on how to set it.
41 - 60 of 80 Posts
that plug is rich, very rich.
Time the car, then see what happens.
Time the car, then see what happens.
Like bone says.
Also, a lot to rich can soot up an O2 sensor and stop it working. They can be cleaned with heat from a slightly lean butane or oxy acetylene flame carefully applied to the correct area.
Also, a lot to rich can soot up an O2 sensor and stop it working. They can be cleaned with heat from a slightly lean butane or oxy acetylene flame carefully applied to the correct area.
that plug is rich, very rich.
Time the car, then see what happens.
Thats what I thought! As you called I was off on both distributor and mechanical timing.Like bone says.
Also, a lot to rich can soot up an O2 sensor and stop it working. They can be cleaned with heat from a slightly lean butane or oxy acetylene flame carefully applied to the correct area.
1 tooth off on mechanical timing (the 3 marks were about 1" to the right of the indicator)
I've fixed that and installed a new bosch oem style O2 sensor already.
While I may be running rich, do you think that the condition of the plugs could be somewhat caused by the same issue causing my blue/white smoke?
If timing doesn't fix the rich condition, what would be the next suggestion to look at? Vacuum leaks? MAP sensor? PCV Valve?
Could a stuck open PCV Valve be causing me to burn oil ?
Oil burning leaves shiny black smooth deposits on the plug, like a coat of paint. Excess fuel leaves flat dull black deposits on the plug like it was dusted down with powder.
As it ran with the cam timing out one tooth, you may have bent valves.
Cam timing being that far out will kill VE and compression. That will impact on fuel metering and combustion efficiency.
Ignition timing being that far out will kill combustion efficiency.
Try it with the timing fixed. Once the soot burns off everything, it might be OK
As it ran with the cam timing out one tooth, you may have bent valves.
Cam timing being that far out will kill VE and compression. That will impact on fuel metering and combustion efficiency.
Ignition timing being that far out will kill combustion efficiency.
Try it with the timing fixed. Once the soot burns off everything, it might be OK
It may not have been a full tooth but it was definitely off.Oil burning leaves shiny black smooth deposits on the plug, like a coat of paint. Excess fuel leaves flat dull black deposits on the plug like it was dusted down with powder.
As it ran with the cam timing out one tooth, you may have bent valves.
Cam timing being that far out will kill VE and compression. That will impact on fuel metering and combustion efficiency.
Ignition timing being that far out will kill combustion efficiency.
Try it with the timing fixed. Once the soot burns off everything, it might be OK
It's looking better already mileage wise, 35 miles and the needle hasn't moved yet before it was at least an 1/8 down.
Repost
With OEM everything as per your OP, how can you possibly change the belt half a tooth, unless you mean one tooth on the cam being half a tooth on the crank.
never even thought of that honestly, guess it was a full tooth.With OEM everything as per your OP, how can you possibly change the belt half a tooth, unless you mean one tooth on the cam being half a tooth on the crank.
ok well I guess my excitement was too soon; at half tank of cautious driving it's only at 90 miles, so it's on track for the same 19/20 mpg ugh
Poor fuel economy due to the engine is normally associated with rich mixture, fuel leaks, retarded ignition, miss fires or poor compression.
Due to chassis it is most often due to dragging brakes but can be low tyre pressures, external accessories like wings, or very large wheels and tyres.
Due to chassis it is most often due to dragging brakes but can be low tyre pressures, external accessories like wings, or very large wheels and tyres.
well my plugs were rich so I have to check if I am still running richPoor fuel economy due to the engine is normally associated with rich mixture, fuel leaks, retarded ignition, miss fires or poor compression.
Due to chassis it is most often due to dragging brakes but can be low tyre pressures, external accessories like wings, or very large wheels and tyres.
no fuel leaks I'm aware of
ignition is on where it needs to be now (was ridiculously retarded before)
compresssion is 175+ on all cylinders
Tires are at 40psi
no additional external accessories or large wheels
is there any way to lean out a stock car? If i'm still running too rich could it be a case of simply swapping ecu's?
It depends why your running rich.
Is your fuel pressure correct.
Is your MAP sensor OK
Are your injectors leaking.
Is it the same ECU that ran OK before.
Is your fuel pressure correct.
Is your MAP sensor OK
Are your injectors leaking.
Is it the same ECU that ran OK before.
Is your AIT sensor working correctly.
Is your oxygen sensor working correctly.
Is your oxygen sensor working correctly.
oxygen sensor is brand new.Is your AIT sensor working correctly.
Is your oxygen sensor working correctly.
IAT I dunno ... will be doing all this testing tomorrow after work as I have college tonight.
Just a thought, while i have 175+ compression numbers, according to the zeal calculator I do have 8.55:1 ish compresstionPoor fuel economy due to the engine is normally associated with rich mixture, fuel leaks, retarded ignition, miss fires or poor compression.
Due to chassis it is most often due to dragging brakes but can be low tyre pressures, external accessories like wings, or very large wheels and tyres.
not having any cooling issues, not sure how that would apply (excuse my ignorance)t-stat stuck open?
could make the car run cold - the car would run a little rich like when your car warms up on a cold day. and you wouldn't have a cooling prob if it were stuck opennot having any cooling issues, not sure how that would apply (excuse my ignorance)
41 - 60 of 80 Posts
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